Principles of Vaccine Interchangeability

Similar vaccines from different manufacturers are routinely authorized for use in Canada. Circumstances such as vaccine shortages, contraindication to a specific vaccine, changes in product availability, or migration across jurisdictions may necessitate giving vaccines from different manufacturers to the same individual over time. Because immunization schedules and specific products used may vary across provinces and territories and between countries, questions about vaccine interchangeability may arise when evaluating the immunization status of persons new to Canada or people who have moved between jurisdictions.

General principles of vaccine interchangeability

In general, use the same manufacturer’s product for all doses in a vaccine series. However, routine immunization should not be deferred because of the lack of availability of a specific product.

To be considered interchangeable, the vaccines should:

be authorized with the same indications and with equally acceptable schedules, and

be authorized for the same population, and

contain comparable antigens, and

be similar in terms of safety, reactogenicity, immunogenicity and efficacy.

Even when vaccines from different manufacturers are authorized for the same indications, the manufacturers may use differing production methods, antigens or antigen concentrations, adjuvants, conjugating proteins, stabilizers and preservatives. Each of these factors could affect the vaccine’s potential for interchangeability.

In general, vaccine diluents are not interchangeable. Lyophilized vaccines should be reconstituted only with the diluent provided for that purpose, unless otherwise permitted by the manufacturer.

Vaccine interchangeability Recommendations

The following recommendations for vaccine interchangeability are applicable only to vaccines with the same indications and authorization for use in the same populations.

Diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b vaccines
Complete the primary series of three doses of diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b-containing vaccine with the same combination vaccine whenever possible. However, if the original vaccine is unknown or unavailable, an alternative combination vaccine may be used to complete the primary series. On the basis of expert opinion, an appropriate product from any manufacturer can be used for all booster doses.

Hepatitis A vaccines
Monovalent hepatitis A vaccines may be used interchangeably. Any hepatitis A vaccine indicated for the age of the vaccinee will provide an effective booster dose after a first dose of vaccine from a different manufacturer.

Hepatitis B vaccines
Monovalent hepatitis B vaccines may be used interchangeably, using the dosage and schedules recommended by the manufacturer for the age group. Combined hepatitis A and hepatitis B vaccine can be used to complete the hepatitis B primary series. Refer to Hepatitis A Vaccine and Hepatitis B Vaccine in Part 4 for appropriate schedules.

Human papillomavirus (HPV) vaccines
Whenever possible, use one manufacturer’s brand of HPV vaccine to complete the vaccine series. If the brand of the previously received doses is not known, either brand of HPV vaccine may be used to complete the vaccine series. Both HPV4 and HPV2 vaccines provide protection against HPV types 16 and18, and will likely achieve protective antibody levels against these HPV types. If fewer than three doses of HPV4 vaccine are administered, protection against HPV types 6 and 11 cannot be ensured. HPV2 vaccine is not recommended for boys and men. Refer to Human Papillomavirus Vaccine in Part 4 for additional information.

Influenza vaccines
If a child (aged less than 9 years) requires 2 doses of influenza vaccine in the same season, it is preferable to use the same type of vaccine (trivalent inactivated [TIV] or live attenuated influenza [LAIV]) for both doses. However, if the child is eligible for either TIV or LAIV, and the type of vaccine used for the first dose is not available, use either type of vaccine for the second dose. If using TIV for both doses, vaccines from different manufacturers can be used for the first and second dose.

Measles, mumps and rubella vaccines
On the basis of expert opinion, the measles-mumps-rubella (MMR) vaccines authorized in Canada may be used interchangeably.

Varicella vaccines
If the child has received only one dose of MMR and one dose of varicella vaccine, or one dose of measles-mumps-rubella-varicella (MMRV) vaccine, then the second dose can be provided as MMRV, or as MMR and varicella vaccine separately. It is recommended that the same manufacturer’s univalent varicella or MMRV vaccine be used to complete the schedule unless the vaccine used for the first dose is unknown or unavailable.

Meningococcal conjugate vaccines
There are no published data regarding the interchangeability of monovalent conjugate meningococcal vaccines, but the vaccines have been safely interchanged without a noticeable decrease in efficacy. When possible, the infant series should be completed with the same vaccine. Either of the quadrivalent conjugate meningococcal vaccines may be used for re-vaccination when indicated, regardless of which meningococcal vaccine was used for initial vaccination.

Pneumococcal conjugate vaccines
Infants who have started an immunization schedule with one conjugate pneumococcal vaccine should continue their immunization schedule with a conjugate pneumococcal vaccine that contains the largest number of pneumococcal serotypes. For example, infants who have started a vaccine series with pneumococcal conjugate 7-valent or pneumococcal conjugate 10-valent vaccine, should have their series completed with pneumococcal conjugate 13-valent vaccine.

Rabies vaccines
Wherever possible, complete a rabies immunization series with the same product. However, if this is not feasible, rabies vaccines are considered interchangeable. People who require a booster dose of rabies vaccine for pre-exposure prophylaxis can be given either vaccine, regardless of the vaccine used for the initial vaccination series.

Rotavirus vaccines
There are no data on safety, immunogenicity, or efficacy when ROTARIX™ (GlaxoSmithKline Inc.) is administered as the first dose and RotaTeq® (Merck Canada Inc.) is used as the second dose or vice versa. Given that the two vaccines differ in composition and schedule, complete the vaccine series with the same product whenever possible. However, in the event that the product used for a previous dose(s) is unknown, complete the series with the available product. If any dose in the series was RotaTeq®, administer a total of 3 doses of vaccine.

Typhoid vaccines
There are no data regarding the interchangeability of oral typhoid vaccines.

Evidence-base for vaccine interchangeability recommendations

Ideally, as new vaccines become available, clinical trials should be conducted evaluating interchangeability with existing products. To date, the majority of information regarding interchangeability has been gathered as a result of situations of vaccine shortages and new product purchases with the negotiation of new contracts. Given the importance of this issue and the limited data available regarding the interchangeability of vaccines, further research in this area is encouraged.

Selected References

Centers for Disease Control and Prevention. General recommendations on immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Morb Mortal Wkly Rep 2011;60(2):1-61.